This invention relates to a separation module for purifying a fluid. Fluid separation devices having an easily replaceable and disposable fluid separation module have been used to control contamination in industrial processes for many years. Such devices are an integral part of the manufacture of many products including pharmaceuticals, food stuffs and beverages. However, nowhere is the need for effective contamination control greater than in the semiconductor fabrication industry. With circuit details in the submicron range and with further feature size reductions inevitable, the need for control of particulate, ionic, organic and other contaminants in the semiconductor process fluids is essential. Also, because semiconductor devices are fabricated in clean rooms, it is important to minimize the potential of contaminating the manufacturing environment. For this reason, disposable fluid separation devices are preferable in semiconductor fabrication processes in order to minimize contamination of the process lines as well as the clean room.
Examples of semiconductor process fluids which are processed at the point of use (POU) include those chemicals used in photolithographic processing (photochemicals). Photochemicals include materials such as primers, adhesion promoters, photoresists, edge bead removers, antireflective coatings, developers, dielectrics, and the like. Such chemicals are commonly dispensed onto the silicon wafer by a specialized pump and subsequently dispersed into a uniform thin film using a process called spin coating. The purity of these chemicals at the POU is essential to producing acceptable product yields.
Fluid separation devices are in general of two types. In the first type, the separation element such as a filter is a replaceable component, while the pressure vessel which houses the element, i.e., the housing, is reusable. The housing also contains appropriate fluid connections to the rest of the fluid processing system. Replacing the fluid separation element requires opening the housing, removing the separation element, installing the replacement separation element into the housing and closing the housing. There are many disadvantages to this type of fluid separation device. First, the replacement operation is time consuming, especially if access to the housing is restricted. Secondly, because the housing contains a quantity of the fluid being processed and because the fluid separation element is usually saturated with the fluid, spillage of the fluid usually occurs. In the case of hazardous fluids, spills can be a threat to the well-being of personnel in the area as well as potentially damaging to nearby equipment and facilities. Finally, the opening of the housing exposes the internal surfaces of the fluid processing system to unwanted contamination from the surrounding environment.
The second type of separation device is one in which the separation element is permanently attached to the housing, which also contains appropriate fluid connections to the rest of the fluid processing system, to form an integrated module. In this case, replacement involves disconnecting the entire separation module from the fluid processing system and reconnecting a replacement module to the system. In this manner, replacement is easier, exposure of the operator to hazardous chemicals is minimized and the reliability of the connection is significantly improved. The type of separation device is referred to as a disposable module, since the whole module is removed and disposed of whenever the separation element requires replacement regardless of what connector design is employed. Disposable modules usually require that multiple connections be made sequentially, a minimum of two connections, and more typically three or four. Threaded fasteners are cumbersome and sometimes difficult to engage; factors which involve the subsequent consumption of additional time and effort. Furthermore, the module has to be held in place while the connections are being made, which makes the connection event even more difficult since it requires performing two actions at the same time (i.e., holding the module in place and attaching each connector sequentially). Finally, in those applications in which the permanent connections to the fluid processing system are not rigid, as for example, when the flexible tubing is used, liquid has a tendency to be discharged as the connections disengage. All of these problems exacerbate the time and effort required to replace a disposable module, in addition to still allowing for exposure of personnel to hazardous materials, and contamination of the manufacturing environment.
For these reasons, some disposable separation modules have been designed with features that allow them to be connected quickly and easily to the fluid processing system in a “quick-connect” fashion. These types of quick-connect modules provide for a set of connectors that sealingly engage with a single, simple stroke or action, to a mating set of connectors attached to a reusable substrate. Different types of mechanisms have been designed to accomplish quick-connect retention, all of which heretofore have required some form of relative motion between the male connector and its female counterpart, most commonly a twisting action.
It has also been proposed to provide a separation module in a system for dispensing a filtered fluid composition wherein the separation module is introduced into a pivotable housing to effect a desired connection. The pivotable housing is expensive and is subjected to breakage over time due to excessive use.
Accordingly, it would be desirable to provide a separation module which can be replaced in a fluid separation system without the need of a pivotable housing.